There are known techniques for displaying images providing a disparity (hereinafter, also referred to as stereo images) to right and left eyes of a viewer, and thereby allowing the viewer to view planar videos as a stereoscopic video.
There are also techniques for generating, from a pair of stereoscopic images, images having viewpoints different from those of the pair (different-viewpoint images) (for example, see Patent Literature 1).
The technique disclosed in Patent Literature 1 is a technique for generating such different-viewpoint images by shifting pixels in horizontal directions in images according to distances in depth directions in the images using depth maps indicating distances in the depth directions. This technique is generally called as Depth Image Based Rendering (DIBR).
The images generated using the DIBR may include areas which do not appear in the original stereoscopic images. The areas do not have assigned pixel values (hereinafter, referred to as hole areas), and thus need to be interpolated using some interpolation process.